A conventional fastening device for mobile phone includes a base adhered to a suction member at one side, and a body at the other side of base capable of up/down pivoting about base having a support member at a distal end with respect to base being also up/down pivotable about base. A magnetic member, embedded on support member, may attract to a foreign object by means of an anti-skid pad mounted thereon. In detail, for example, a mobile phone may be put on the anti-skid pad. As such, the magnetic force produced by the magnetic member may attract the battery compartment of mobile phone for securing mobile phone to the pad. Thus, the mobile phone is not susceptible to fall. However the previous design suffered from several disadvantages:
1) The fastening device can only pivot up/down, while horizontal pivoting is not possible. As such, user should first separate suction member from the attached object. Then adjust the horizontal angle of the fastening device to a desired one. Finally, place suction member on the object again. This achieves the task of adjusting the horizontal position of the fastening device with mobile phone mounted thereon. In view of the foregoing, it bothers user very much. PA1 2) The length of body is fixed, i.e., not a telescopic one. As such, such fastening device sometimes may not suit user's needs. PA1 3) The signal receiving performance of mobile phone may be adversely affected because, as stated above, the magnetic force produced by the magnetic member attracts the battery compartment of mobile phone for securing mobile phone thereon. Further, the magnetic force of magnetic member may cause an abnormal operation of electronics of mobile phone and even damage data stored in Subscriber Identity Module (SIM) card of mobile phone which in turn prevents mobile phone from operating normally.